Another man and woman were being questioned tonight about a double murder linked to dissident republican terrorists in Belfast.
The pair were arrested by detectives hunting the killers of Edward Burns, 36, who was shot in the head and dumped in the west of the city.
Police have linked his murder to that of Joey Jones, 38, who was battered to death in the Ardoyne district of North Belfast.
Both bodies were discovered earlier this month and their deaths are believed to be due to heightening tensions within splinter republican paramilitary organisations.
The latest arrests were made following searches of a house in the Whitecliff Parade area of West Belfast.
A number of items, including a suspected firearm, were also seized during the raid and taken for further examination.
Yesterday police also detained a man and a woman for questioning about the killings.
Mr Jones, from Poleglass on the western edge of Belfast, had been severely beaten and police recovered a spade near the scene.
The second victim, Mr Burns, who was from Ardoyne, was found in a car park off the Falls Road near a Gaelic Athletic Association club.